Pivot construction



A ril 14, 1942.- J. w. PAGE! PIVOT CONS' IR UCTION Fiied Dec. 5, 1940 3 Sheets-Sheet l April14,'1942. .J.W.PAGE Y 2,219,133 19 1 PIVOT CONSTRUCTION Filed Deb. 5, 1940 3 Sheets-Shet. 2

Z/ fiverfir. i 0 Z/ l April 14, 1942. J w, PAGE I 2,279,839

' 7' 'PIVOT CONSTRUCTION I F iled Dec. 5, 1940 :5 Sheets-Sheet 3 Mr I Patented Apr. 14, 1942 rear oFFlcs PIVOT CONSTRUGTION John W. Page, Chicago, IlL, assignor to Page Engineering Company,

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a corporation of Illi- Dplication December 5, 1940, Serial No. 368,701

(CL. 3.Q8l'14 1) 4 Claims.

This invention relates to improvements in pivot construction and more especially to such construction particularly applicable for use in connection with excavating machinery, derricks and the like mounted on platforms. The invention is moreparticularly adapted for use in connection with such heavy machinery which is mobile. The invention may be used, for example, in connection with walking mechanism of any kind in which the supporting platform (upon. which the machinery is rotatably mounted) is lifted from thegound in connection with moving the mechanism. Such'walking mechanism, for example, isshown in my copending application Serial No. 84,205, filed June 8, 1936, and in my Patent 2,164,- 120, issued June 27, 1939. In various forms of mechanism of this general type in which the machineryhouse or platform is pivotally mounted upon a base or tub, such base or tub is lifted from the ground at various times during the moving or walking of the device so that it hangs from the pivot.

The pivot construction, therefore, must be very heavy and rugged because apparatus of the kind here under consideration usually weighs several tons. When the machine is resting on the base the pivot valso must take considerable lateral strain because of the thrusts imposed thereon by the digging apparatus. This is especially true where a drag-line bucket is used.

Among the features of my invention is the making of such pivot construction of simplified design but very rugged so as to withstand the strains imposed upon the same by digging and by the weight of the tub or platform when the latter is lifted from the ground.

Another feature of the invention is the making of such pivot construction to permit easy adjustment of the same and easy detachment of the pivot for replacement or repair purposes.

Other features and advantages of my invention will appear more fully as I proceed with my specification.

In that forms of device embodying the features of my invention shown in the accompanying drawings, Fig. 1 is a view in side elevation, partly in section; Fig. 2 is an enlarged sectional view of the pivot construction; Fig. 3 is a view taken as indicated by the line 3 of Fig. 2; Fig. 4 is a View taken as indicated by the line 4 of Fig. 2; Fig. 5 is a view taken as indicated by the line 5 of Fig. 2; and Fig. 6 is a view taken as indicated by the line 6 of Fig. 2.

As shown in the drawings, l0 indicates a base or tub resting on the ground II when the machine is digging. This base supports the machinery platform |2 which is rotatably mounted on the base in the usualmanner by wheels l3 operating between the circular tracks l4 and I5. A machinery house |2d is ordinarily mounted on theplatform I 2.

The pivot construction between the base H.) and platform l2 to which this invention relates is more particularly shown in Figs. 2-6. This construction shows a concave bearing seat I6 carried by the platform |2 with an aperture |6a therethrough and a similar concave bearing seat 11, carried by the base ID, with an aperture |'|'a therethrough. 8 indicates a pivot pin extending through said apertures. On the upper end of the pivot pin is a nut 9 having a convex bearing surface l-9a engaging the concave surface |6b on the bearing seat I6. 20 indicates a locking member for the nut l9 having a squared opening 20a engaging the reduced squared end |8a of the pin |8 to prevent rotation thereon. The locking member 20 is provided with a depending flange or skirt 20b provided with internal notches 20c engaging teeth |9b on the nut l9 to prevent relative rotation. It will be seen, therefore, that with the locking member in the position shown in Fig.

2, rotation of the nut I9 on the pin I8 is pre- I vented.

The lower end of the pivot l8 carries another nut 2|. 22 indicates a locking member for the lower nut having a convex bearing surface 22:; engaging the concave surface Nb of the bearing seat When the base is lifted from the ground, the locking member 22 is held in looking position by pressure of the bearing seat against the nut 2|. When in such locking position the nut 2| is held against rotation for the following reasons.

|8b indicates teeth on the pivot pin I8 engaged by co-acting teeth on the locking member 22; and the latter with a depending flange or skirt 222) provided with teeth 22c engaging teeth 2|a on the nut 2| so that when the locking member 22 is in the position shown in solid lines in Fig. 2 the nut2| will be locked against rotation.

The base III is provided with an upwardly projecting sleeve Illa in which the pivot I8 is loosely fitted. On this sleeve is mounted a bearing 2a carried by the socket |2b depending from the platform l2. The bearing |2a is mounted for universal movement in the socket |2b; and said bearing is capable of vertical sliding movement and rotational movement on the sleeve Illa.

In Fig. 2 the parts are shown in the position they occupy when the base Ill is raised from the ground and hangs on the pivot. It will be seen that the nut l9 can be unlocked by merely lifting the locking member 20 off the end of the pin or shaft l8. When thus unlocked the nut I9 can be loosened from the pin allowing the pin to be dropped. Assuming that the base In is suitably supported on the ground or by other means, such dropping of the pin |8 will move the lower end 2| away from the seat I1 giving space therebetween topermit-the locking member 22 to be raised from the nut 2| so that the latter will be unlocked. The pivot pin |8 can then be unscrewed from the nut 2|. The nut 2| is pref erably held against'rotation by being provided with a square flange 2|b held against rotation by the members |||b in the base. Vertical movelower nut having a bearing surface on its upper ment of the nut 2| in the base, however, is permitted.

The nut I! can be removed from the upper member out of locking engagement when the nut and pivot H! are permitted to have relative rotation.

The sleeve Illa is rigidly mounted on the base ||l so that lateral stresses imposed by the digging operation will be taken. by thissleeve through the bearing |2a thereon; and the universal mounting of the bearing in the socket |2b will permit some rocking of the platform I! on said bearing. v 1

, While I have shown and described certain embodiments of my invention, it is, to be understood that it is capable of many modifications. Changes, therefore, in the construction and arrangement may be made without departing from the spirit and scope of the invention as disclosed in the appended claims, in which it is my intention to claim all novelty, inherent in my invention as broadly as permissible, in view of the prior art.

What I claim as new, and desire to secure by Letters Patent is:

1. Pivot construction, including: upper and lower members, each carrying a bearing seat with an aperture therethrough; a pivot pin extending through said apertures; an upper nut on the upper end of the pivot pin having a bearing surface on its lower face engagingthe bearing seat on the upper member; a locking member for the upper nut; a lower nut on the lower end of the pivot pin; and a locking member for the face engaging the bearing seat on the lower member.

2. Pivot construction, including: upper and lower members, each carrying a concave bearing seat with an aperture therethrough; a pivot pin extending through said apertures; an upper nut on the upper end of the pivot pin having a convex bearing surface on its lower face engaging the bearing seat on the upper member; a looking member for the upper nut; a lower nut on the lower end of the pivot pin; and a locking member forthe lower nut having a convex bearing surface'on its upper face engaging the bearing seat on thelower member.

3. Construction as claimed in claim 1 in which the lower member has an upstanding sleeve surrounding the pivot pin and the upper member carries a bearing on said sleeve.

4, Construction as claimed in claim 1 in which the lower member has an upstanding sleeve surrounding thepivot pin and the upper member carries a bearing on said sleeve, said bearing being mounted on said upper member for universal movement with respect thereto.

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